In search of the perfect sheet metal concentric drilled hole

[A2022]

In search of the perfect sheet metal concentric step drilled hole. I have found that it is not easy to drill a perfectly concentric hole for step up hole sizes. a drill flute can catch on one side and dig in and then the hole is not concentric. I have found that high drill speed and a light pressure seems to work best along with a small incremental step drill to the hold center position. I am trying the cobalt alloy vs HSS step drill to see if there is any difference. Perhaps the cobalt alloy Unibit will hold the edge longer.

[A2022]

this guy says the Temo step drill is the best performer.

Best Step Bit I’ve Ever Tested Destroys $123 Snap On Blue Point!
https://youtu.be/zjtSdJsC4aM?si=5aKvcYLPRv3bg1oW

case of 6 for $100, cobalt
https://www.amazon.com/TEMO-Cobalt-Spir ... 101&sr=1-8